Make file locations appear in zebrad error messages

[teor2345]

Motivation

When Zebra's Rust test harness fails in CI, I can't see the file and line in the panic backtrace:

12: zebra_test::command::TestChild<T>::expect_stdout_line_matches::h471f18611d79fb45
    at <unknown source file>:<unknown line>
13: acceptance::lightwalletd_integration_test::h1e497ff748a26c03
    at <unknown source file>:<unknown line>

https://github.com/ZcashFoundation/zebra/runs/7992118921?check_suite_focus=true#step:6:246

This happens in both Docker, and in release builds on my local machine.

The application panicked (crashed).
Message:  Opening database "/home/.../.cache/zebra/state/v25/mainnet" failed: Error { message: "IO error: While lock file: /home/.../.cache/zebra/state/v25/mainnet/LOCK: Resource temporarily unavailable" }. Hint: Check if another zebrad process is running. Try changing the state cache_dir in the Zebra config.
Location: zebra-state/src/service/finalized_state/disk_db.rs:460
...
  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ BACKTRACE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
                                ⋮ 7 frames hidden ⋮                               
   8: zebra_state::service::finalized_state::disk_db::DiskDb::new::h0adc7941d0b09e1e
      at <unknown source file>:<unknown line>
   9: zebra_state::service::finalized_state::FinalizedState::new::hd85ae10e187a7755
      at <unknown source file>:<unknown line>
...

But debug builds on my local machine show the file locations:

9: zebra_state::service::finalized_state::disk_db::DiskDb::new::hfc24129cd47798c6
      at /home/dev/zebra/zebra-state/src/service/finalized_state/disk_db.rs:<unknown line>
  10: zebra_state::service::finalized_state::zebra_db::ZebraDb::new::hcc01b459aaf10f3f
      at /home/dev/zebra/zebra-state/src/service/finalized_state/zebra_db.rs:50
  11: zebra_state::service::finalized_state::FinalizedState::new::hbcbdd50bfd733126
      at /home/dev/zebra/zebra-state/src/service/finalized_state.rs:84

Tasks

Try adding debugging info to the Rust release profile:

zebra/Cargo.toml

Line 67 in 5866fc3

[profile.release]

[teor2345]

This makes diagnosing errors in the docker tests tricky, but it can wait until next sprint.

[teor2345]

This important, but it's not causing any particular issues right now.

[mpguerra]

@gustavovalverde does it make sense to look at this issue opportunistically since we're making other changes to the Dockerfile? Especifically this part:

Try changing the build working directory to the zebrad source directory:

zebra/docker/Dockerfile

Line 12 in 5866fc3

WORKDIR /opt/zebrad

[gustavovalverde]

After I'm done with #5933 I might add this one, as #5933 is pilling up with untagged images in the Registry.

[teor2345]

@gustavovalverde @mpguerra I just re-checked this on my local machine, and it happens in all release builds, even outside Docker.

So I don't think we can fix it by changing the Docker config.

[teor2345]

I had a look at this, we can fix this issue using the debug setting in .cargo/config.toml:
https://doc.rust-lang.org/cargo/reference/profiles.html#debug

But the debug info adds 300 MB to the zebrad binary, making it 11 times its usual 29 MB size. I'm not sure if that's worth it. (For comparison, zcashd is 18 MB.)

Since this hasn't been a blocker for diagnosing any bugs, I made it into a branch which developers can use if we need it:
https://github.com/ZcashFoundation/zebra/tree/detailed-backtraces